Overwrite the default list support

The default list support provided by browsers in edit mode has two main issues:

• The generated HTML is invalid. The following is a sample of the HTML generated:

  <ul>
    <li>a</li>
    <ul>
      <li>b</li>
      <ul>
        <li>c</li>
      </ul>
    </ul>
  </ul>
  

• The list detection and behavior is messed up when the editor has as input a valid HTML for nested lists. The following messes up the editor:

  <ul>
    <li>a
      <ul>
        <li>b
          <ul>
            <li>c</li>
          </ul>
        </li>
      </ul>
    </li>
  </ul>
  

While the first issues can be fixed by effective cleaning on the server side, the second requires us to overwrite the default list support.

Side note: The second issue can be found in the latest release of FCKeditor.